FIG 2. The effect of D/H and H/S ratios on general shape.

A, For a D/H ratio value less than 1, the observed shape is an ellipse, with the major axis in the vertical direction; for a value of 1, a circle; and for values greater than 1, an ellipse, with the major axis in the horizontal direction.

B, For an H/S value less than 2, the aneurysm has a pear shape; for a value of 2, a circle; and for a value greater than 2, a beehive shape.